Volume measurement apparatus and method

ABSTRACT

Embodiments of the invention generally provide an electrochemical processing system configured to provide selected amounts of electrolyte composition components for single plating process. The selected amounts of components to be added to an electrolyte composition may be achieved by a volume measurement device using an ultrasonic sensor to measure volume of a vessel.

BACKGROUND OF THE INVENTION

1. Field of the Invention

Embodiments of the invention generally relate to an electrochemicalprocessing system and methods for electrochemically depositingconductive materials on substrates.

2. Description of the Related Art

Metallization of sub-quarter micron sized features is a foundationaltechnology for present and future generations of integrated circuitmanufacturing processes. More particularly, in devices such as ultralarge scale integration-type devices, i.e., devices having integratedcircuits with more than a million logic gates, the multilevelinterconnects that lie at the heart of these devices are generallyformed by filling high aspect ratio, i.e., greater than about 4:1,interconnect features with a conductive material, such as copper oraluminum. Conventionally, deposition techniques such as chemical vapordeposition (CVD) and physical vapor deposition (PVD) have been used tofill these interconnect features. However, as the interconnect sizesdecrease and aspect ratios increase, void-free interconnect feature fillvia conventional metallization techniques becomes increasinglydifficult. Therefore, plating techniques, i.e., electrochemical plating(ECP) and electroless plating, have emerged as promising processes forvoid free filling of sub-quarter micron sized high aspect ratiointerconnect features in integrated circuit manufacturing processes.

In an ECP process, for example, sub-quarter micron sized high aspectratio features formed into the surface of a substrate (or a layerdeposited thereon) may be efficiently filled with a conductive material,such as copper. ECP plating processes are generally two stage processes,wherein a seed layer is first formed over the surface features of thesubstrate, and then the surface features of the substrate are exposed toan electrolyte solution, while an electrical bias is applied between theseed layer and a copper anode positioned within the electrolytesolution. The electrolyte solution generally contains ions to be platedonto the surface of the substrate, and therefore, the application of theelectrical bias causes these ions to be urged out of the electrolytesolution and to be plated onto the biased seed layer, thus depositing alayer of the ions on the substrate surface that may fill the features.Electrolyte solutions also include chemical components to improve iontransition into and out of the electrolyte solution, to improvedeposition rates, and to develop desired deposition profiles.

However, electrolyte solutions are sensitive to the changes in thelevels of components of the composition. Minor changes in thecompositions may result in compositions having variable deposition ratesand less than desirable deposition profiles. Prior processes forintroducing chemical components to electrolyte compositions have lessthan desired results, including concentration spikes and non-uniformityof electrolyte composition at the point of use. The prior processes canresult in less than desirous deposition results, and excess use ofelectrolyte composition, which can result in increase cost ofconsumables and operation costs.

Additionally, previous systems for precisely measuring volumes to beadded to electrolyte solutions have utilized fixed volumes ofdeliveries, which are unsuitable for effectively and efficientlyinstituting changes in constituent composition of electrolyte solutionswithout hardware modification.

Therefore, there is a need for an improved electrochemical platingsystem configured to provide electrolyte compositions for anelectrochemical plating process.

SUMMARY OF THE INVENTION

Embodiments of the invention generally provide an electrochemicalprocessing system configured to provide measured amounts of chemicalcomponents, electrolyte compositions, or both for a plating process orother chemical processes including surface preparation processes, suchas substrate cleaning, etching or deoxidizing. In one aspect, a methodis provided for supplying a fluid to a substrate processing apparatusincluding measuring a first level in the vessel with a first ultrasonicsignal to provide a first volume measurement, delivering at least onechemical component to the vessel, measuring a second level in the vesselwith a second ultrasonic signal to provide a second volume measurement,determining the difference in volume between the first volumemeasurement and the second volume measurement, comparing the differencein volume with a pre-determined value, and discharging chemicalcomponents from the vessel to the substrate processing apparatus.

In another aspect, a method is provided for electroplating at least onelayer onto a surface of a substrate surface including positioning thesubstrate in a plating cell on a unitary system platform for a platingtechnique, supplying an electrolyte composition to the plating cell bysupplying an electrolyte and an amount of one or more chemicalcomponents, wherein the amount of one or more chemical components areprovided by measuring the first level of a vessel with a firstultrasonic signal to provide a first volume measurement, delivering atleast one chemical component to the vessel, measuring a second level inthe vessel with a second ultrasonic signal to provide a second volumemeasurement, determining the difference in volume between the firstvolume measurement and the second volume measurement, comparing thedifference in volume with a pre-determined value, and dischargingchemical components from the vessel to the plating cell, and depositinga conductive material from the electrolyte composition to the surface ofthe substrate.

In another aspect, an electrochemical processing system is providedincluding a system platform having one or more processing cellspositioned thereon, at least one robot positioned to transfer substratesbetween the one or more processing cells, and a fluid delivery system influid communication with each of the one or more processing cells, thefluid delivery system including one or more chemical component sources,a metering pump in fluid communication with each of the chemicalcomponent sources, an electrolyte source in fluid communication with themetering pump, and a vessel in fluid communication with the meteringpump at an input and with the one or more processing cells at an output,the vessel comprising a charging cell, an ultrasonic sensor, and acontroller.

In another aspect, an electrochemical processing system is providedincluding a processing system base having one or more process celllocations thereon, at least two electrochemical plating cells positionedat two of the process cell locations, at least one spin rinse dry cellpositioned at one of the process cell locations, at least one substratebevel clean cell positioned at another one of the process celllocations, and a fluid delivery system in fluid communication with eachof the one or more processing cells, the fluid delivery system includingone or more chemical component sources, a metering pump in fluidcommunication with each of the chemical component sources, a firstvirgin electrolyte source in fluid communication with the metering pump,and a vessel in fluid communication with the metering pump at an inputand with one or more processing cells at an output, the vesselcomprising a charging cell, an ultrasonic sensor, and a controller.

BRIEF DESCRIPTION OF THE DRAWINGS

So that the manner in which the above recited features of the presentinvention can be understood in detail, a more particular description ofthe invention, briefly summarized above, may be had by reference toembodiments, some of which are illustrated in the appended drawings. Itis to be noted, however, that the appended drawings illustrate onlytypical embodiments of this invention and are therefore not to beconsidered limiting of its scope, for the invention may admit to otherequally effective embodiments.

FIG. 1 is a top plan view of one embodiment of an electrochemicalplating system of the invention;

FIG. 2A is a partial sectional view of one embodiment of anelectrochemical process cell;

FIG. 2B is a partial sectional view of another embodiment of anelectrochemical process cell;

FIG. 3 is a schematic diagram of one embodiment of a plating solutiondelivery system;

FIG. 4A is a schematic diagram of one embodiment of a volume measurementdevice;

FIG. 4B is a perspective view of one embodiment of a volume measurementdevice;

FIG. 5 is a partial sectional view of one embodiment of a process cellconfigured to remove deposited material from an edge of a substrate;

FIG. 6 is a partial sectional view of one embodiment of a process cellconfigured to spin, rinse and dry a substrate; and

FIG. 7 is a flow diagram illustrating one embodiment of a process formonitoring chemical component volume.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Embodiments of the invention generally provide an electrochemicalplating system configured to plate conductive materials, such as metals,on a semiconductor substrate using a device for accurately measuringcomponent quantities, for example, for use in apparatus implementingmultiple chemistries on a single plating platform. Embodiments of theinvention contemplate that the measurement device may be used formeasuring, adding, or mixing chemical components for various platingprocesses, including, but not limited to direct plating on a barrierlayer, alloy plating, alloy plating combined with convention metalplating, plating on a thin seed layer, optimized feature fill and bulkfill plating, plating multiple layers with minimal defects, or any otherplating process where more than one chemistry may be beneficial to aplating process.

While the following description of the volume measurement device isdirected to use in an electrochemical processing system (ECP), theinvention contemplates the use of the invention where precise volumes ofliquids may be added to form processing composition. For example thevolume measurement device may be used in combination with chemicalmechanical polishing apparatus, such as the Mirra® Mesa™ polishingsystem and the Reflexion™ processing system, commercially available fromApplied Materials, Inc., of Santa Clara, Calif., wet clean processapparatus, such as the Tempest™ wet clean apparatus available fromApplied Materials, Inc., of Santa Clara, Calif., and other liquidprocessing systems.

FIG. 1 is a top plan view of one embodiment of an electrochemicalprocessing system (ECP) 100 of the present invention. ECP system 100generally includes a processing base 113 having a robot 120 centrallypositioned thereon. The robot 120 generally includes one or more robotarms 122, 124 configured to support substrates thereon. Additionally,the robot 120 and the accompanying blades 122, 124 are generallyconfigured extend, rotate, and vertically move so that the robot 120 mayinsert and remove substrates to and from a plurality of processinglocations 102, 104, 106, 108, 110, 112, 114, 116 positioned on the base113.

ECP system 100 further includes a factory interface (FI) 130. FI 130generally includes at least one FI robot 132 positioned adjacent a sideof the FI that is adjacent the processing base 113. This position ofrobot 132 allows the robot to access substrate cassettes l34 to retrievea substrate 126 therefrom and then deliver the substrate 126 to one ofprocessing cells 114, 116 to initiate a processing sequence. Similarly,robot 132 may be used to retrieve substrates from one of the processingcells 114, 116 after a substrate processing sequence is complete. Inthis situation robot 132 may deliver the substrate 126 back to one ofthe cassettes 134 for removal from the system 100. Additionally, robot132 is also configured to access an anneal chamber 135 positioned incommunication with FI 130. The anneal chamber 135 generally includes atwo position annealing chamber, wherein a cooling plate-or position 136and a heating plate or position 137 are positioned adjacently with asubstrate transfer robot 140 positioned proximate thereto, e.g., betweenthe two stations. The robot 140 is generally configured to movesubstrates between the respective heating 137 and cooling plates 136.

Generally, process locations 102, 104, 106, 108, 110, 112, 114, 116 maybe any number of processing cells utilized in an electrochemical platingplatform. More particularly, the process locations may be configured aselectrochemical plating cells, rinsing cells, bevel clean cells, spinrinse dry cells, substrate surface cleaning cells, electroless platingcells, metrology inspection stations, and other cells or processes thatmay be beneficially used in conjunction with a plating platform.

FIG. 2A is a cross sectional view of one embodiment of a processing cell(FIG. 2A illustrates an exemplary electrochemical plating cell) that maybe implemented in any one of processing locations 102, 104, 106, 108,110, 112, 114, 116 of processing system 100 as shown in FIG. 1.Generally, however, the exemplary processing system 100 is configured toinclude four electrochemical plating cells at processing locations 102,104, 112, and 110. Processing locations 106 and 108 are generallyconfigured as edge bead removal or bevel clean chambers. Further,processing locations 114 and 116 are generally configured as substratesurface cleaning chambers and spin rinse dry chambers, which may bepositioned in a stacked manner, i.e., one above the other. However, theinvention is not intended to be limited to any particular order orarrangement of cells, as various combinations and arrangements may beimplemented without departing from the scope of the invention.

Returning to FIG. 2A, the electrochemical processing cell 150 generallyincludes a head assembly 211, an anode assembly 220, an inner basin 272,and an outer basin 240. The outer basin 240 is coupled to a base 160 andcircumscribes the inner basin 272. The inner and outer basins 272, 240are typically fabricated from an electrically insulative materialcompatible with process chemistries, for example, ceramics, plastics,plexiglass (acrylic), lexane, PVC, CPVC or PVDF. Alternatively, theinner and outer basins 272, 240 may be made from a metal, such asstainless steel, nickel or titanium, which is coated with an insulatinglayer, such as Teflon®, fluoropolymer, PVDF, plastic, rubber and othercombinations of materials compatible with plating fluids and can beelectrically insulated from the electrodes (i.e., the anode and cathodeof the electroplating system). The inner basin 272 is typicallyconfigured to conform to the substrate plating surface and the shape ofthe substrate being processed through the system, generally having acircular or rectangular shape. In one embodiment, the inner basin 272 isa cylindrical ceramic tube having an inner diameter that has about thesame dimension as or slightly larger than the diameter of a substratebeing plated in the cell 150. The outer basin 272 generally includes achannel 248 for catching plating fluids flowing out of the inner basin272. The outer basin 272 also has a drain 218 formed therethrough thatcouples the channel 248 to a reclamation system for processing,recycling and/or disposal of used plating fluids.

The head assembly 211 is mounted to a head assembly frame 252. The headassembly frame 252 includes a mounting post 254 and a cantilever arm256. The mounting post 254 is coupled to the base 160 and the cantileverarm 256 extends laterally from an upper portion of the mounting post 254and is generally adapted to rotate about a vertical axis of the mountingpost 254 to allow movement of the head assembly 211 over or clear of thebasins 240, 272. The head assembly 211 is generally attached to amounting plate 260 disposed at the distal end of the cantilever arm 256.The lower end of the cantilever arm 256 is connected to a cantilever armactuator 268, such as a pneumatic cylinder, mounted on the mounting post254. The cantilever arm actuator 268 provides pivotal movement of thecantilever arm 256 with respect to the joint between the cantilever arm256 and the mounting post 254. When the cantilever arm actuator 268 isretracted, the cantilever arm 256 moves the head assembly 211 away fromthe anode assembly 220 disposed in the inner basin 272 to provide thespacing required to remove and/or replace the anode assembly 220 fromthe first process cell 150. When the cantilever arm actuator 268 isextended, the cantilever arm 256 moves the head assembly 211 axiallytoward the anode assembly 220 to position the substrate in the headassembly 211 in a processing position. The head assembly 211 may alsotilt to orientate a substrate held therein in at an angle fromhorizontal.

The head assembly 211 generally includes a substrate holder assembly 250and a substrate assembly actuator 258. The substrate assembly actuator258 is mounted onto the mounting plate 260, and includes a head assemblyshaft 262 that extends downwardly through the mounting plate 260. Thelower end of the head assembly shaft 262 is connected to the substrateholder assembly 250 to position the substrate holder assembly 250 in aprocessing position and in a substrate loading position. The substrateassembly actuator 258 additionally may be configured to provide rotarymotion to the head assembly 211. In one embodiment, the head assembly211 is rotated between about 2 rpm and about 50 rpm during anelectroplating process, and may be rotated between about 5 and about 20rpm. The head assembly 211 can also be rotated as the head assembly 211is lowered to position the substrate in contact with the platingsolution in the process cell as well as when the head assembly 211 israised to remove the substrate from the plating solution in the processcell. The head assembly 211 may be rotated at a high speed (i.e., >20rpm) after the head assembly 211 is lifted from the process cell toenhance removal of residual plating solution from the head assembly 211and substrate.

The substrate holder assembly 250 generally includes a thrust plate 264and a cathode contact ring 266. The cathode contact ring 266 isconfigured to electrically contact the surface of the substrate to beplated. Typically, the substrate has a seed layer of metal, such ascopper, deposited on the feature side of the substrate. A power source246 is coupled between the cathode contact ring 266 and the anodeassembly 220 and provides an electrical bias that drives the platingprocess.

The thrust plate 264 and the cathode contact ring 266 are suspended froma hanger plate 236. The hanger plate 236 is coupled to the head assemblyshaft 262. The cathode contact ring 266 is coupled to the hanger plate236 by hanger pins 238. The hanger pins 238 allows the cathode contactring 266 when mated against the inner basin 272, to move to closer tothe hanger plate 236, thus allowing the substrate held by the thrustplate 264 to be sandwiched between the hanger plate 236 and thrust plate264 during processing, thereby ensuring good electrical contact betweenthe seed layer of the substrate and the cathode contact ring 266.

The anode assembly 220 is generally positioned within a lower portion ofthe inner basin 272 below the substrate holder assembly 250. The anodeassembly 220 generally includes one or more anodes 244 and a diffusionplate 222. The anode 244 is typically disposed in the lower end of theinner basin 272 and the diffusion plate 222 is disposed between theanode 244 and the substrate held by the substrate holder assembly 250 atthe top of the inner basin 272. The anode 244 and diffusion plate 222are generally maintained in a spaced-apart relation by insulative spacer224. The diffusion plate 222 is typically attached to and substantiallyspans the inner opening of the inner basin 272. The diffusion plate 222is generally permeable to the plating solution and is typicallyfabricated from a plastic or ceramic material, for example an olefinsuch as a spunbonded polyester film: The diffusion plate 222 generallyoperates as a fluid flow restrictor to improve flow uniformity acrossthe surface of the substrate 126 being plated. The diffusion plate 222also operates to damp electrical variations in the electrochemical cell,i.e., to control electrical flux, which improves plating uniformity.Alternatively, the diffusion plate 222 may be: fabricated from ahydrophilic plastic, such as treated PE, PVDF, PP, or other porous orpermeable material that provides electrically resistive dampingcharacteristics.

The anode assembly 220 may include a consumable anode 244 that serves asa metal source for the plating process. Alternatively, the anode 244 maybe a non-consumable anode, and the metal to be electroplated is suppliedwithin the plating solution from the plating solution delivery system111. The anode assembly 220 may be a self-enclosed module having aporous enclosure preferably made of the same metal as the metal to beelectroplated, such as copper. Alternatively, the enclosure may befabricated from porous materials, such as ceramics or polymericmembranes. Exemplary consumable and non-consumable anodes includecopper/doped copper and platinum, respectively. The anode 244 istypically metal particles, wires, and/or a perforated sheet and istypically manufactured from the material to be deposited on thesubstrate, such as copper, aluminum, gold, silver, platinum, tungsten,copper phosphate, noble metal or other materials which can beelectrochemically deposited on the substrate. The anode 244 may beporous, perforated, permeable or otherwise configured to allow passageof the plating solution therethrough. Alternatively, the anode 244 maybe solid. As compared to a non-consumable anode, the consumable (i.e.,soluble) anode provides gas-generation-free plating solution andminimizes the need to constantly replenish the metal in the platingsolution. In the embodiment depicted in FIG. 2A, the anode 244 is asolid copper disk.

An electrolyte inlet 216 is formed through the inner basin 272 and iscoupled to the plating solution delivery system 111. The platingsolution entering the inner basin 272 through the electrolyte inlet 216flows through or around the anode assembly 220 upward toward the surfaceof the substrate 126 positioned on the upper end of the inner basin 272.The plating solution flows across the substrate's surface and throughslots (not shown) in the cathode contact ring 266 to a passage formed inthe outer bas in 240. The bias applied by the power source 246 betweenthe substrate (through the cathode contact ring 266) and the anodes 244causes metal ions from the plating fluids and/or anode to deposit on thesurface of the substrate. Examples of process cells that may be adaptedto benefit from the invention are described in U.S. patent applicationSer. No. 09/905,513, filed Jul. 13, 2001, and in U.S. patent applicationSer. No. 10/061,126, filed Jan. 30, 2002, both of which incorporated byreference in their entireties.

FIG. 2B is partial sectional view of another embodiment of an exemplaryprocessing cell, and more particularly, an exemplary electrochemicalplating cell 200. The electrochemical plating cell 200 generallyincludes an outer basin 201 and an inner basin 202 positioned withinouter basin 201. Inner basin 202 is generally configured to contain aplating solution that is used to plate a metal, e.g., copper, onto asubstrate during an electrochemical plating process. During the platingprocess, the plating solution is generally continuously supplied toinner basin 202 (at about 1 gallon per minute for a 10 liter platingcell, for example), and therefore, the plating solution continuallyoverflows the uppermost point of inner basin 202 and runs into outerbasin 201. The overflow plating solution is then collected by outerbasin 201 and drained therefrom for recirculation into inner basin 202.Plating cell 200 is generally positioned at a tilt angle, i.e., theframe portion 203 of plating cell 200 is generally elevated on one sidesuch that the components of plating cell 200 are tilted between about 3°and about 30°. Therefore, in order to contain an adequate depth ofplating solution within inner basin 202 during plating operations, theuppermost portion of basin 202 may be extended upward on one side ofplating cell 200, such that the uppermost point of inner basin 202 isgenerally horizontal and allows for contiguous overflow of the platingsolution supplied thereto around the perimeter of basin 202.

The frame member 203 of plating cell 200 generally includes an annularbase member 204 secured to frame member 203. Since frame member 203 iselevated on one side, the upper surface of base member 204 is generallytilted from the horizontal at an angle that corresponds to the angle offrame member 203 relative to a horizontal position. Base member 204includes an annular or disk shaped recess formed therein, the annularrecess being configured to receive a disk shaped anode member 205. Basemember 204 further includes a plurality of fluid inlets/drains 209positioned on a lower surface thereof. Each of the fluid inlets/drains209 are generally configured to individually supply or drain a fluid toor from either the anode compartment or the cathode compartment ofplating cell 200. Anode member 205 generally includes a plurality ofslots 207 formed therethrough, wherein the slots 207 are generallypositioned in parallel orientation with each other across the surface ofthe anode 205. The parallel orientation allows for dense fluidsgenerated at the anode surface to flow downwardly across the anodesurface and into one of the slots 207. Plating cell 200 further includesa membrane support assembly 206. Membrane support assembly 206 isgenerally secured at an outer periphery thereof to base member 204, andincludes an interior region configured to allow fluids to passtherethrough. A membrane 208 is stretched across the support 206 andoperates to fluidly separate a catholyte chamber and anolyte chamberportions of the plating cell. The membrane support assembly may includean o-ring type seal positioned near a perimeter of the membrane, whereinthe seal is configured to prevent fluids from traveling from one side ofthe membrane secured on the membrane support 206 to the other side ofthe membrane. A diffusion plate 210 is positioned above the membrane 208and is configured similarly to diffusion plate 222 illustrated in FIG.2A.

In operation, assuming a tilted implementation is utilized, the platingcell 200 will generally immerse a substrate into a plating solutioncontained within inner basin 202. Once the substrate is immersed in theplating solution, which generally contains copper sulfate, chlorine, andone or more of a plurality of organic plating chemical components(levelers, suppressors, accelerators, etc.) configured to controlplating parameters, an electrical bias is applied between a seed layeron the substrate and the anode 205 positioned in the plating cell. Theelectrical bias is generally configured to cause metal ions movingthrough the plating solution to deposit on the cathodic substratesurface. In this embodiment of the plating cell 200, separate fluidsolutions are supplied to the volume above the membrane 208 and thevolume below the membrane 208. Generally, the volume above the membraneis designated the cathode compartment or region, as this region is wherethe cathode electrode or plating electrode is positioned. Similarly, thevolume below the membrane 208 is generally designated the anodecompartment or region, as this is the region where the anode is located.The respective anode and cathode regions are generally fluidly isolatedfrom each other via membrane 208 (which is generally an ionic membrane).Thus, the fluid supplied to the cathode compartment is generally aplating solution containing all the required constituents to supportplating operations, while the fluid supplied to the anode compartment isgenerally a solution that does not contain the plating solution chemicalcomponents that are present in the cathode chamber, e.g., copper sulfatesolutions, for example. Additional detail with respect to theconfiguration and operation of the exemplary plating cell illustrated inFIG. 2B may be found in commonly assigned U.S. patent application Ser.No. 10/268,284, entitled “Electrochemical Processing Cell”, filed onOct. 9, 2002.

FIG. 3 is a schematic diagram of one embodiment of the plating solutiondelivery system 111. The plating solution delivery system 111 isgenerally configured to supply a plating solution to each processinglocation on system 100 that requires the solution. More particularly,the plating solution delivery system is further configured to supply adifferent plating solution or chemistry to each of the processinglocations. For example, the delivery system may provide a first platingsolution or chemistry to processing locations 110, 112, while providinga different plating solution or chemistry to processing locations 102,104. The individual plating solutions are generally isolated for usewith a single plating cell, and therefore, there are no crosscontamination issues with the different chemistries. However,embodiments of the invention contemplate that more than one cell mayshare a common chemistry that is different from another chemistry thatis supplied to another plating cell on the system. These features areadvantageous, as the ability to provide multiple chemistries to a singleprocessing platform allows for multiple chemistry plating processes on asingle platform.

In another embodiment of the invention, a first plating solution and aseparate and different second plating solution can be providedsequentially to a single plating cell. Typically, providing two separatechemistries to a single plating cell requires the plating cell to bedrained and/or purged between the respective chemistries; however, amixed ratio of less than about 10 percent first plating solution to thesecond plating solution should not be detrimental to film properties.

More particularly, the plating solution delivery system 111 typicallyincludes a plurality of chemical component sources 302 and at least oneelectrolyte source 304 that are fluidly coupled to each of theprocessing cells of system 100 via a valve manifold 332. Typically, thechemical component sources 302 include an accelerator source 306, aleveler source 308, and a suppressor source 310. The accelerator source306 is adapted to provide an accelerator material that typically adsorbson the surface of the substrate and locally accelerates the electricalcurrent at a given voltage where they adsorb. Examples of acceleratorsinclude sulfide-based molecules. The leveler source 308 is adapted toprovide a leveler material that operates to facilitate planar plating.Examples of levelers are nitrogen containing long chain polymers. Thesuppressor source 310 is adapted to provide suppressor materials thattend to reduce electrical current at the sites where they adsorb(typically the upper edges/corners of high aspect ratio features).Therefore, suppressors slow the plating process at those locations,thereby reducing premature closure of the feature before the feature iscompletely filled and minimizing detrimental void formation. Examples ofsuppressors include polymers of polyethylene glycol, mixtures ofethylene oxides and propylene oxides, or copolymers of ethylene oxidesand propylene oxides.

In order to prevent situations where a chemical component source runsout and to minimize chemical component waste during containersreplacement, each of the chemical component sources 302 generallyincludes a bulk or larger storage container coupled to a smaller buffercontainer 316. The buffer container 316 is generally filled from thecontainers 306, 308, and 310, and therefore, the containers 306, 308,and 310, may be removed for replacement without affecting the operationof the fluid delivery system, as the associated buffer container maysupply the particular chemical component to the system while thecontainers are being replaced. The volume of the buffer container 316 istypically much less than the volume of the containers 306, 308, and 310.The containers 306, 308, and 310 are sized to contain enough chemicalcomponents for 10 to 12 hours of uninterrupted operation. This providessufficient time for operators to replace the containers when thecontainers are empty. If the buffer container was not present anduninterrupted operation was still desired, the containers would have tobe replaced prior to being empty, thus resulting in significant chemicalcomponent waste.

In the embodiment depicted in FIGS. 3, 4A, and 4B, the fluid deliverysystem includes a volume measurement module 312 coupled between theplurality of chemical component sources 302 and the plurality ofprocessing cells (not shown). The volume measurement module 312generally includes at least a vessel 610, an ultrasonic sensor 620disposed in a position to monitor the level or volume in the vessel 610,a controller 630 coupled to the ultrasonic sensor 620, a liquid inletport 315, a liquid outlet port 340, a purge port 317, a gas inlet 640,and a vent 313. The volume measurement module 312 may be adapted toreceive liquids from one or more sources and adapted for providingvolumes of individual liquids and mixtures of liquids.

The vessel 610 may comprise any container adapted for repeated fluidflow therethrough and may be of any shape or configuration. Typically,the vessel 610 includes a cylindrical volumetric shape having multiplefluid inlets and outlets. The vessel 610 may be of any material inert tothe fluids being flowed therethrough including stainless steel, glass,and plastic. All components of the volume measurement module 312 maycomprise plastic. If redundant sensors are used, such as opticalsensors, the vessel 610 preferably comprises a transparent material tothe optical measurement device or an independent visual scale of volumedisposed on the vessel surface, such as graduated volume markings. Thevolume may vary on the amount of chemical components to be charged to anelectrolyte solution, and may comprise between about 1 milliliters andabout 1000 milliliters in volume, such as between about 4 ml and about120 ml. An example of the vessel 610 is a charge tube having a 1.375inch outer diameter with a 7.5 inch height, with 4 or 5 inlets andoutlets.

The ultrasonic sensor 620 may be a fixed level sensor disposed along avertical axis of the circumference or side of the vessel 610. Theultrasonic sensor may also be a variable level sensor and disposedvertically displaced from a central axis of the vessel 610 to read thesurface level of any liquid disposed in the vessel 610. For example, theultrasonic sensor may be disposed on the top of the vessel 610 as shownin FIGS. 4A and 4B. An example of a variable level ultrasonic sensorincludes the FM-600 and FM-900 series of ultrasonic sensors commerciallyavailable from Hyde Park Electronics of Dayton, Ohio, having a 10-0Vanalog output and an 18 mm outer diameter. In operation, the variablelevel ultrasonic sensor emits an ultrasonic signal, reads any reflectingor returning signal, or echo, of the emitted ultrasonic signal, todetermine a level in the container, converts the level reading to avoltage, and sends an analog voltage signal to a controller 630.Alternatively, the signal may be a serial communications signal (i.e.,RS-232, RS-485, etc.), or a well-known industrial protocol bus signal,such as the General Purpose Interface Bus (GPIB). The sensor may be usedto measure the amount of liquid in the vessel 610 during filling thevessel 610, after an amount of liquid has been metered in the vessel610, or during the discharge of the liquid to the desired process orcell. Alternatively, a pressure sensor positioned or coupled fluidicallyto the bottom of the vessel 610 to sense the liquid column pressure headof the vessel 610 may be used to measure the volume in the vessel 610.An example of a pressure sensor is a model 209, part 2091001EG1M2805,pressure sensor from Setra Systems, Inc., of Boxborough, Md.

A temperature measurement device (not shown), such as a thermistor, mayalso be disposed on or adjacent the vessel 610 for measuring thetemperature inside the vessel 610. The temperature measurement devicemay be positioned to measure the non-liquid filled volume of the vessel610, such as at top of the vessel 610 near the vent 313. The temperaturemeasurement device may be integrated into the ultrasonic sensor 620 ordisposed in an external spaced relationship from the ultrasonic sensor620. The temperature measurement device may be adapted to provide datato sensor 620 or the controller 630 to compensate for changes in thevelocity of sound with temperature and provide a more accuratemeasurement of the level and volume of any chemical components orliquids in the vessel 610. When the temperature measurement signal isrouted to the ultrasonic sensor 620 prior to the controller 630, theultrasonic signal can be compensated for temperature variancesrepresented by the temperature measurement signal to form atemperature-corrected output signal from the sensor 620 to thecontroller 630. One example of a thermistor comprises an epoxythermistor with a protruding heads having two leads connected to thethermistor and the two leads seated in a polymeric sheath, such as aPeek Tubing, and sealed from exposure by an epoxy, such as MasterbondEP21AR Epoxy.

A controller 630 may be coupled to the sensor 620, or any other sensorsincluding the temperature measurement device, to receive signalstherefrom. The controller 630 may be any suitable controller capable ofreceiving signals from the sensor 620 and calculating a volume foreffectively determining the fluctuating state of liquid volume in thevessel 610 for one or more steps. The controller 630 may be anindependent controller or integrated in part of whole in any controllerused to monitor and control the processing apparatus. For someembodiments, the controller may be a programmable logic controller (PLC)or a rack-mounted personal computer (PC). In one example, the controller630 may comprise a central processing unit (CPU), memory, and interfacecircuitry. The CPU may be one of any form of computer processor that canbe used in an industrial setting. The memory may be one or more ofreadily available computer-readable medium, such as random access memory(RAM), read only memory (ROM), floppy disk, hard disk, or any other formof digital storage, local or remote.

A first liquid inlet port 315 is coupled to a chemical component dosingpump 311 disposed between the volume measurement module 312 and thechemical component sources 306, 308, and 310. The chemical componentdosing pump 311 provides the chemical components to the vessel 610 viathe pump line 319 and may also be adapted to provide additional liquids,such as electrolyte 304, deionized water, 342, and/or a purge gas 344.The chemical component dosing pump 311 may be a rotary metering pump, asolenoid metering pump, a diaphragm pump, a syringe, a peristaltic pump,a piston pump, or other positive displacement volumetric device. Thechemical component dosing pump 311 may used in conjunction with thevolume measurement device 312 and/or the controller described herein aswell as used singularly or coupled to a flow sensor. For example, in oneembodiment, the chemical component dosing pump 311 includes a rotatingand reciprocating ceramic piston that drives 0.32 ml per cycle of apredetermined chemical component. Alternatively, the dosing pump 311 maybe replaced by pressurized fluid delivery process or a vacuum deliverysystem, which draws chemical components into the module 312 by a vacuumsource at port 313 or another port. The electrolyte source 304 may alsobe fluidly coupled to the vessel 610 by the dosing pump 311.

A first outlet port 330 of the volume measurement module 312 isgenerally coupled to the processing cells via valve or valve manifold332 by an output line 340. Chemical components (i.e., at least one ormore accelerators, levelers and/or suppressors) may be mixed ordelivered for combining with an electrolyte flowing through a firstdelivery line 350 from the electrolyte source 304, to form the first brsecond plating solutions as desired. The purge port 317 is generallycoupled to the vessel 610 by the valve or manifold 335 electrolytesource 304. The purge port 317 may be used to purge vessel 610 whennecessary to recover from chemical component delivery errors that aredetected by the volume measurement module 312.

A first gas inlet line 640 may be used to couple a purge/processing gassource 660 to the vessel 610. The purge/processing gas generallycomprises a pressurized inert gas to purge gas disposed in portions ofthe vessel 610 not containing a liquid. The pressurized inert gas may beadapted to provide inert gases of variable pressures based on the use ofthe inert gases. The purge/processing gas may also be used to assist inevacuating the liquid volume from the vessel 610 to the processingcells. A vent line 313 may also be used to allow removal of gases in thevessel 610, such as residual gases, contaminant gases, or “head” gases,for example, during a purge process or during volumetric fill in thevessel 610. The purging of contaminant gases is believed to minimizeultrasonic measurement variations.

While the volume measurement module 312 is described herein forprocessing chemical components for electrolyte solutions, the inventioncontemplates that the volume measurement module 312 may be used forprocessing additional liquids used in plating operations, includingelectrolytes, cleaning agents, such as water, etchants as describedherein, or dissolving agents as described herein, among others.

In operation, the volume measurement module 312 receives, measures, anddischarges chemical components to an electrolyte for use in a platingprocess. A purge gas from source 660 is introduced into the vessel 610to remove gases therefrom by vent 313. The sensor 620 then measures thelevel of any fluids located in the vessel 610. Chemical components arethen introduced from the sources 306, 308, 310, through the buffercontainer 316 to the dosing pump 311 and through the dosing pump line319 into the vessel 610. The sensor 620 measures the level of the liquidin the vessel 610 either continuously, periodically, or as a levelsensor until a specified volume is measured. The vent 313 is closed, thefirst outlet port 330 is opened and a pressurized gas from the inert gassource 660 or electrolyte from source 304 is introduced into the vessel610 to discharge liquids therefrom. The sensor 620 may also measure thedischarging liquid volume.

While not shown, the invention also contemplates additional componentsusing in fluid systems, including bypass valves, purge valves, flowcontrollers, and/or temperature controllers.

In another embodiment of the invention the fluid delivery system may beconfigured to provide a second completely different plating solution andassociated chemical components. As such, while not shown, multiplevolume measurement modules 312 may be disposed in the system to connectto one or more of the plating cells to provide the necessary platingsolutions. For example, in this embodiment a different base electrolytesolution (similar to the solution contained in container 304) may beimplemented to provide the processing system 100 with the ability, forexample, to use plating solutions from two separate manufacturers.Further, an additional set of chemical component containers may also beimplemented to correspond with the second base plating solution.Therefore, this embodiment of the invention allows for a first chemistry(a chemistry provided by a first manufacturer) to be provided to one ormore plating cells of system 100, while a second chemistry (a chemistryprovided by a second manufacturer) is provided to one or more platingcells of system 100. Each of the respective chemistries will generallyhave their own associated chemical components, however, cross dosing ofthe chemistries from a single chemical component source or sources isnot beyond the scope of the invention.

In order to implement the fluid delivery system capable of providing twoseparate chemistries from separate base electrolytes, a duplicate of thefluid delivery system illustrated in FIG. 3 is connected to theprocessing system. More particularly, the fluid delivery systemillustrated in FIG. 3 is generally modified to include a second set ofchemical component containers 302 and separate sources for virgin makeupsolution/base electrolyte 304 are also provided. The additional hardwareis set up in the same configuration as the hardware illustrated in FIG.3, however, the second fluid delivery system is generally in parallelwith the illustrated or first fluid delivery system. Thus, with thisconfiguration implemented, either base chemistry with any combination ofthe available chemical components may be provided to any one or more ofthe processing cells of system 100.

The valve manifold 332 is typically configured to interface with a bankof valves 334. Each valve of the valve bank 334 may be selectivelyopened or closed to direct fluid from the valve manifold 332 to one ofthe process cells of the plating system 100. The valve manifold 332 andvalve bank 334 may optionally be-configured to support selective fluiddelivery to additional number of process cells. In the embodimentdepicted in FIG. 3, the valve manifold 332 and valve bank 334 include asample port 336 that allows different combinations of chemistries orcomponent thereof utilized in the system 100 to be sampled withoutinterrupting processing.

In some embodiments, it may be desirable to purge the volume measurementmodule 312, output line 340 and/or valve manifold 332. To facilitatesuch purging, the plating solution delivery system 111 is configured tosupply at least one of a cleaning and/or purging fluid. In theembodiment depicted in FIG. 3, the plating solution delivery system 111includes a deionized water source 342 and a non-reactive gas source 344coupled to the first delivery line 350. The non-reactive gas source 344may supply a non-reactive gas, such as an inert gas, air or nitrogenthrough the first and second delivery lines 350 and 352 to flush out thevalve manifold 332. Deionized water may be provided from the deionizedwater source 342 to flush out the valve manifold 332 in addition to, orin place of non-reactive gas. Electrolyte from the electrolyte sources304 may also be utilized as a purge medium.

In an alternative embodiment of the system, a second delivery line 352is tied between the first gas delivery line 350 and the dosing pump 311.A purge fluid of a purge liquid includes at least one of an electrolyte,deionized water or other suitable liquid from the respective sources,such as 304 and 342, may be diverted from the first delivery line 350through the second gas delivery line 352, and through the dosing pump311 to the volume measurement module 312. A purge fluid of a purge gas,such as nitrogen gas, from the respective sources 344 may be divertedfrom the first delivery line 350 through the second gas delivery line352 and purge gas line 351 to the volume measurement module 312. Thepurge fluid is driven through the volume measurement module 312 and outthe output line 340 to the valve manifold 332. The valve bank 334typically directs the purge fluid out a drain port 338 to thereclaimation system 232. The various other valves, regulators and otherflow control devices have not been described and/or shown for the sakeof brevity.

In one embodiment of the invention, chemical components for a firstchemistry may be provided to promote feature filling of copper on asemiconductor substrate. The first chemistry may include between about30 and about 65 g/l of copper, between about 35 and about 85 ppm ofchlorine, between about 20 and about 40 g/l of acid, between about 4 andabout 7.5 ml/L of accelerator, between about 1 and 5 ml/L of suppressor,and no leveler. The chemical components for the first chemistry isdelivered from the valve manifold 332 to a first plating cell 150 toenable features disposed on the substrate to be substantially filledwith metal. As the first chemistry generally does not completely fillthe feature and has an inherently slow deposition rate, the firstchemistry may be optimized to enhance the gap fill performance and thedefect ratio of the deposited layer.

A second chemistry makeup with a different chemistry from the firstchemistry may be provided to another plating cell on system 100 viavalve manifold 332, wherein the second chemistry is configured topromote planar bulk deposition of copper on a substrate. The secondchemistry may include between about 35 and about 60 g/l of copper,between about 60 and about 80 ppm of chlorine, between about 20 andabout 40 g/l of acid, between about 4 and about 7.5 ml/L of accelerator,between about 1 and about 4 ml/L of suppressor, and between about 6 andabout 10 ml/L of leveler, for example. The chemical components for thesecond chemistry is delivered from the valve manifold 332 to the secondprocess cell to enable an efficient bulk metal deposition process to beperformed over the metal deposited during the feature fill andplanarization deposition step to fill the remaining portion of thefeature. Since the second chemistry generally fills the upper portion ofthe features, the second chemistry may be optimized to enhance theplanarization of the deposited material without substantially impactingsubstrate throughput. Thus, the two step, different chemistry depositionprocess allows for both rapid deposition and good planarity of depositedfilms to be realized. The two chemistries may be provided sequentiallyfrom the same volume measurement module 312.

When utilized with a process cell requiring anolyte solutions such asthe process cell 200 of FIG. 2B, the plating solution delivery system111 generally includes an anolyte fluid circuit 380 that is coupled tothe inlet 209 of the plating cell 200. The anolyte fluid circuit 380 mayinclude a plurality of chemical component sources 382 coupled by adosing pump 384 to a manifold 386 that directs chemical components(typically not utilized) selectively metering from one or more of thesources 382 and combined with an anolyte in the manifold 386 to thoseprocess cells (such as the cell 200) requiring anolyte solution duringthe plating process. The anolyte may be provided by an anolyte source388 and a volume measurement module may be used to provide theselectively metering chemical components.

FIG. 5 depicts one embodiment of a process cell 400 configured to removedeposited material from an edge of a substrate 402. The process cell 400includes a housing 404 having a substrate chuck 406 disposed therein.The substrate chuck 406 includes a plurality of arms, shown as 408A-C,extending from a central hub 410. Each arm 408A-C includes a substrateclamp 412 disposed at a distal end of the arm. The hub 410 is coupled bya shaft 414 to a motor 416 disposed outside of the housing 404. Themotor 416 is adapted to rotate the chuck 406 and substrate 402 disposedthereon during processing. During processing, the substrate 402 isrotated while an etchant is delivered from an etchant source 418 to thesubstrate's edge. The etchant is typically delivered to the substrate'sedge through a plurality of upper nozzles 420 positioned within thehousing 404 in an orientation that directs the etchant flowing therefromin a radially outward direction against the substrate's surface. Theprocess cell 400 may also include a plurality of lower nozzles 422coupled to the etchant source 418 and adapted to direct etchant to thesubstrate's edge on the side of the substrate opposite the upper nozzle420. The etchant is typically delivered to the substrate 402 while thesubstrate rotates between about 100 to about 1,000 rpm. The nozzles 420,422 are typically configured to direct the etchant at the substrate in asubstantially tangential direction, typically with an angle of about 10to about 70 degrees, or alternatively, between about 10 and about 30degrees, wherein the angle is defined as being between the substratesurface and the direction or longitudinal axis of the fluid flow ordispensing nozzle. In one embodiment, the etchant is a combination of anacid and oxidizer, such as sulfuric acid, nitric acid, citric acid, orphosphoric acid combined with hydrogen peroxide, which removes depositedcopper from the exclusion zone of the substrate (generally the outerannulus of the substrate surface, which is generally about 2 mm or 3 mmwide.

After the deposited material has been removed from the substrate's edge,deionized water or other cleaning agent is provided through the nozzles420, 422 to clean the substrate's surface. The substrate 402 istypically rotated at approximately 200 rpm to remove etchant, deionizedwater and other impurities from the respective upper and lower surfacesof the substrate 402. The various fluids dispended during processing aredrained from the housing 404 through a port 425 formed in the bottom ofthe housing 404. Two process cells configured to remove depositedmaterial from the edge of the substrate which may be adapted to benefitfrom the invention are described in U.S. patent application Ser. No.09/350,212, filed Jul. 9, 1999, and U.S. patent application Ser. No.09/614,406, filed Jul. 12, 2000, both of which are hereby incorporatedby reference in their entireties.

FIG. 6 is a partial sectional view of a process cell 500 configured tospin, rinse and dry a substrate 502 after processing. The process cell500 includes a housing 504 having a substrate chuck 506 disposedtherein. The substrate chuck 506 includes a plurality of arms, shown as508A-C, extending from a central hub 510. Each arm 508A-C includes asubstrate clamp 512 disposed at a distal end of the arm. The hub 512 iscoupled by a shaft 514 to a motor 516 disposed outside of the housing504. The motor 516 is adapted to rotate the chuck 506 and substrate 502disposed thereon during processing. During processing, the substrate isrotated while a cleaning agent, such as deionized water or alcohol, isdelivered from a fluid source 518 to the upper side of the substrate 502from a plurality of upper nozzles 520 positioned within the housing 504above the chuck 506. The backside of the substrate 502 is treated withat least one of a cleaning agent or a dissolving agent dispensed from aplurality of lower nozzles 522 disposed below the chuck 506 and coupledto the fluid source 518. Examples of dissolving agents includehydrochloric acid, sulfuric acid, phosphoric acid, hydrofluoric acidamong others. The fluids are typically delivered to the substrate whilethe substrate rotates between about 4 to about 4,000 rpm.

After the deposited material has been removed from the substrate's edge,deionized water or other cleaning agent is provided through the nozzles520, 522 to clean the substrate's surface. The substrate 502 istypically rotated at approximately 100 to about 5000 rpm to dry thesubstrate while removing liquids and other impurities from therespective upper and lower surfaces of the substrate 502. The variousfluids dispended during processing are drained from the housing 504through a port 524 formed in the bottom of the housing 504. One processcell configured to clean and dry the substrate which may be adapted tobenefit from the invention is described in U.S. Pat. No. 6,290,865,issued Sep. 18, 2001, which is hereby incorporated by reference in itsentirety.

In operation, embodiments of the invention generally provide a platingsystem having multiple plating cells on a single integrated platform,wherein a fluid delivery system for the plating system is capable ofproviding multiple chemistries to the plating cells. More particularly,for example, assuming that four individual plating cells are positionedon a common system platform, then the fluid delivery system of theinvention is capable of providing a different chemistry to each of thefour plating cells. The different chemistries may include different basesolutions or virgin makeup solutions, and further, may include variouschemical components at various amounts, including absence of selectedchemical components.

Multiple chemistry capability for a single platform has advantages inseveral areas of semiconductor processing. For example, the ability toprovide multiple chemistries to multiple plating cells on a unitaryplatform allows for a single plating system take advantage of positivecharacteristics of multiple chemistries in a single platform on a singlesubstrate. Multiple chemistry capability has application, for example,to feature fill and bulk fill process, as a first plating solution orchemistry may be tailored to a feature full process (low defect, butslow deposition rate process), while a second solution may be tailoredto a feature bulk fill process (a more rapid deposition process that maybe implemented once the feature is primarily filled by the firstprocess). Additionally, a multiple chemistry plating system wouldfacilitate plating directly on barrier layers, as a first platingchemistry could be used to facilitate adhesion of a first material tothe barrier layer, and then a second chemistry could be used plate asecond material over the first material layer on top of the barrierlayer and fill the features without encountering barrier layer platingadhesion challenges. Further, a multiple chemistry system would also bebeneficial to an alloy plating process, wherein a first chemistry couldbe used to plate the alloy layer and then a second chemistry could beused to plate a different layer or another alloy layer over thepreviously deposited layer. Further still, a multiple chemistry processcould be used to substantially improve defect ratios in semiconductorsubstrate plating processes via utilization of a first chemistryconfigured to plate a first layer with minimal defects, and then asecond chemistry configured to plate a second layer over the first layerwith minimal defects in manner that optimizes throughput.

Exemplary Method of the Volume Measurement Module

FIG. 7 is a flow diagram illustration one embodiment of an exemplarymethod 700 for monitoring and controlling the volume of a liquid in thevolume measurement module 312 to the process cells described herein. Themethod may be monitored and controlled by controller 630 as describedherein as well as by any other controller use on the system 100.

The process begins by confirming that chemical components are primed tobe delivered to the vessel 610 of the volume measurement module 312 atstep 710. The confirmation may be achieved, for example, by a proximity,flow, level, or pressure sensor disposed in the chemical componentsources 306, 308, 310, or buffer container 316, in the line between thedosing pump 311 and the chemical component sources 306, 308, 310, orbuffer container 316, or a sensor disposed in or adjacent the dosingpump 311.

A volume of initial fluid is introduced into the vessel 610 at step 720.The electrolyte, for example, catholyte, or deionized water, may beintroduced into the vessel 610, such as less than about 10 ml, forexample, between about 1 and about 2 ml, at step 720. A purge gas of aninert gas, such as nitrogen, is introduced into the vessel 610 to removeany gas, such as head gas, disposed in the vessel 610 and dischargedfrom the vessel 610 through the vent 313 at step 730.

The ultrasonic sensor 620 measures the initial volume of any liquid inthe volume at step 740. For example, an ultrasonic sensor 620 emits anultrasonic signal into the vessel 610. The ultrasonic signal thencontacts the volume of liquid and a reflection signal is generated. Theultrasonic sensor has a receiver to sense reflective signal and basedupon a determination of signal intensity and/or duration betweenemission and reception of the signal, produce an electronic signal, suchas a voltage measurement, representative of liquid level in the vessel610. The electronic signal is typically the average of several hundredreading taken over approximately a time span, for example, between about1 to 2 second time span. The multiple readings are believed to averageout random errors. The ultrasonic sensor 620 may be programmed toaverage multiple reading for example, averaging between 2 and about 1000readings. The controller 630 may also be programmed to average signalsreceived from the ultrasonic sensor 620.

The electronic signal is then sent to the controller 630 as an analogsignal, which is then converted by the controller into a volumemeasurement by use of a prior calibration, a pre-selected value, ordatabase of pre-calculated to pre-measured volumes. Circuitry on theultrasonic sensor or controller may comprise any combination of analogto digital (A/D) converters, digital signal processing (DSP) circuitsand communication circuits to convert the signals to a format suitableby the CPU of the controller. The initial fluid introduced in step 720may be used to provide sufficient signal feedback to establish aninitial level measurement.

Alternatively, if a temperature measuring device, such as a thermistor,is used with the ultrasonic sensor, the thermistor measures thetemperature of the non-liquid filled portion of the vessel 610 tocompensate or correct for the changes in the velocity of sound withtemperature prior to calculating the liquid level in the vessel 610.

One or more chemical components, either concurrently or sequentially,are introduced into the vessel 610 at step 750. The introduced chemicalcomponents level in the vessel 610 is then measured at step 760. Thechemical components levels may be measured as described in step 740.

The volume of the chemical components as determined by the controller630 is compared with a pre-determined or pre-selected value at step 770.If the calculated volume does not achieve the desired pre-determined orpre-selected value, chemical components are continued to be supplied tothe vessel 610. The chemical components may be provided periodically orcontinuously to the vessel 610. Volume calculations may be madeperiodically or continuously during filling of the vessel 610. Thecomparison of values may be used to determine whether the deliveryaccuracy from the pump 311 is correct, and if not, the components in thevessel 610, may be discharge to a drain via line 317. The predeterminedvalue may be the estimated volume provided by an upstream metering pump,such as pump 311, or other delivery mechanism. The predetermined valuemay also be stored electronically in a database for comparison or thecontroller 630 might be able to directly compare values from a sensor onthe pump 311 to the volume measured in the vessel 610.

The process may be repeated for each chemical component introduced intothe vessel 610, so that a final discharge volume may comprise one ormore chemical components that have been pre-mixed before discharge tothe appropriate line, process cell, or storage unit. For example, thedosing pump 311 may provide a metered amount of liquid to the vessel610, a level measurement may be taken for each metered amount or after aseries of metered amount to verify the amount of liquid provided.

The process may be performed statically or dynamically. In a staticprocess, the vessel 610 is filled with a first quantity of fluid and ameasurement is taken of the volume prior to the addition of anyadditional liquids. This can be used to verify the volume metered out bythe dosing pump 311. In a static process, steps 750-770 are performedseparately. In a dynamic process, the vessel is continuously filled witha liquid and the level is continuously of periodically measured until adesired level is reached. In the dynamic process, step 750-770 areperformed concurrently.

If the calculated volume achieves the desired pre-determined orpre-selected value, the contents in the vessel 610 may be discharged atstep 780. The discharge of the contents may be provided by closing thevent 313 of the vessel 610 remaining open during filling of the vessel610, opening an outlet, and pressurizing the liquid from the vessel 610.The liquid may be discharged by supplying pressurized purge gas, such asnitrogen, by the use of deionized water, or by an amount of electrolyte,such as catholyte, provided to the vessel 610.

Optionally, after discharge of the liquids from the vessel 610, thevessel 610 may be rinsed by electrolyte, such as the catholyte, ordeionized water at step 790 prior to initiation of the next sequence.

While the foregoing is directed to embodiments of the present invention,other and further embodiments of the invention may be devised withoutdeparting from the basic scope thereof, and the scope thereof isdetermined by the claims that follow. REFERENCE NUMERALS ECP System 100Process Location 102 Process Location 104 Process Location 106 ProcessLocation 108 Process Location 110 Delivery System 111 Process Location112 Processing Base 113 Process Location 114 Process Location 116 Robot120 Robot Arms 122 Robot Arms 124 Substrate 126 Factory Interface (F1)130 F1 Robot 132 Substrate Cassettes 134 Anneal Chamber 135 CoolingPlate Position 136 Heating Plate Position 137 Processing Cell 150 Base160 Plating Cell 200 Outer Basin 201 Inner Basin 202 Frame Portion 203Base Member 204 Anode Member 205 Support Assembly 206 Slots 207 Membrane208 Fluid Inlet/Drains 209 Diffusion Plate 210 Head Assembly 211Electrolyte Inlet 216 Drain 218 Anode Assembly 220 Diffusion Plate 222Insulative Spacer 224 System 232 Hanger Plate 236 Hanger Pins 238 Basins240 Anodes 244 Power Source 246 Channel 248 Holder Assembly 250 AssemblyFrame 252 Mounting Post 254 Cantilever Arm 256 Assembly Actuator 258Mounting Plate 260 Assembly Shaft 262 Thrust Plate 264 Contact Ring 266Arm Actuator 268 Inner Basin 272 Component Sources 302 ElectrolyteSource 304 Accelerator Source 306 Leveler Source 308 Suppressor Source310 Volume Measurement Module 312 Vent 313 Liquid Inlet Port 315 BufferContainer 316 Purge Port 317 Pump Line 319 First Outlet Port 330 ValveManifold 332 Valve Bank 334 Port 336 Drain Port 338 Output Line 340Water Source 342 Gas Source 344 Delivery Lines 350, 352 Circuit 380Sources 382 Dosing Pump 384 Anolyte Source 388 Process Cell 400Substrate 402 Housing 404 Substrate Chuck 406 Arms 408A-C Central Hub410 Clamp 412 Shaft 414 Motor 416 Etchant Source 418 Nozzles 420, 422Port 425 Process Cell 500 Substrate 502 Housing 504 Chuck 506 Arms508A-C Central Hub 510 Clamp or Hub 512 Shaft 514 Motor 516 Fluid Source518 Upper Nozzles 520 Lower Nozzles 522 Port 524 Vessel 610 Vent 613Sensor 620 Controller 630 Gas Inlet Line 640 Gas Source 660 PrimingAdditive for Delivery to a Vessel 710 Introducing a Volume of InitialLiquid to the 720 Vessel Purging the Vessel of any Resident Gases 730Measuring the Initial Level/Volume of Any 740 Liquid Disposed in theVessel by an Ulatrasonic Sensor Introducing One or More Additives intothe 750 Vessel Measuring the Level/Volume of Additives 760 Disposed inthe Vessel by an Ulatrasonic Sensor Comparing the Level/Volume of theInitial 770 Additives Level/Volume to a Pre-Selected Value to DetermineProcess Volume Discharging the Additives from the Vessel 780 Optionally,Cleaning the Vessel 790

1. A method for supplying a fluid to a substrate processing apparatus,the method comprising: measuring a first level in the vessel with afirst ultrasonic signal to provide a first volume measurement;delivering at least one chemical component to the vessel; measuring asecond level in the vessel with a second ultrasonic signal to provide asecond volume measurement; determining the difference in volume betweenthe first volume measurement and the second volume measurement;comparing the difference in volume with a pre-determined value; anddischarging chemical components from the vessel to the substrateprocessing apparatus.
 2. The method of claim 1, further comprisingdelivering a catholyte to the vessel prior to measuring the volume inthe vessel with the first ultrasonic signal.
 3. The method of claim 2,further comprising purging gas from the vessel prior to measuring thevolume in the vessel with the first ultrasonic signal.
 4. The method ofclaim 1, wherein the discharging chemical components from the vessel tothe substrate processing apparatus comprises closing a vent, opening adischarge valve, and pressure discharging the chemical components by amaterial selected from the group of an inert gas, water, or anelectrolyte composition.
 5. The method of claim 1, wherein the substrateprocessing apparatus comprises a plating cell, an unitary plating systemplatform, or a spin-rinse processing cell.
 6. The method of claim 1,wherein the measuring the level in the vessel with the first ultrasonicsignal further comprises measuring the temperature in the vessel.
 7. Themethod of claim 1, further comprising continuously delivering the atleast one chemical component to the vessel and measuring the level inthe vessel until the pre-determined value is achieved.
 8. A method forelectroplating at least one layer onto a surface of a substrate surface,the method comprising: positioning the substrate in a plating cell on aunitary system platform for a plating technique; supplying anelectrolyte composition to the plating cell by supplying an electrolyteand an amount of one or more chemical components, wherein the amount ofone or more chemical components are provided by: measuring the firstlevel of a vessel with a first ultrasonic signal to provide a firstvolume measurement; delivering at least one chemical component to thevessel; measuring a second level in the vessel with a second ultrasonicsignal to provide a second volume measurement; determining thedifference in volume between the first volume measurement and the secondvolume measurement; comparing the difference in volume with apre-determined value; and discharging chemical components from thevessel to the plating cell; and depositing a conductive material fromthe electrolyte composition to the surface of the substrate.
 9. Themethod of claim 8, further comprising delivering a catholyte to thevessel prior to measuring the volume in the vessel with the firstultrasonic signal.
 10. The method of claim 8, further comprising purginggas from the vessel prior to measuring the volume in the vessel with thefirst ultrasonic signal.
 11. The method of claim 8, wherein thedischarging chemical components from the vessel to the substrateprocessing apparatus comprises closing a vent, opening a dischargevalve, and pressure discharging the chemical components by a materialselected from the group of an inert gas, water, or an electrolytecomposition.
 12. The method of claim 8, wherein the substrate processingapparatus comprises a plating cell, an unitary plating system platform,or a spin-rinse processing cell.
 13. The method of claim 8, furthercomprising rinsing the substrate.
 14. The method of claim 13, furthercomprising spin drying the substrate.
 15. The method of claim 8, whereinthe measuring the level in the vessel with the first ultrasonic signalfurther comprises measuring the temperature in the vessel.
 16. Themethod of claim 8, further comprising continuously delivering the atleast one chemical component to the vessel and measuring the level inthe vessel until the pre-determined value is achieved.
 17. Anelectrochemical processing system, comprising: a system platform havingone or more processing cells positioned thereon; at least one robotpositioned to transfer substrates between the one or more processingcells; and a fluid delivery system in fluid communication with each ofthe one or more processing cells, the fluid delivery system comprising:one or more chemical component sources; a metering pump in fluidcommunication with each of the chemical component sources; anelectrolyte source in fluid communication with the metering pump; and avessel in fluid communication with the metering pump at an input andwith the one or more processing cells at an output, the vesselcomprising a charging cell, an ultrasonic sensor, and a controller. 18.The apparatus of claim 17, wherein the one or more chemical componentsources further comprise: a first source for providing anelectrochemical plating accelerator; a second source for providing anelectrochemical plating leveler; and a third source for providing anelectrochemical plating suppressor.
 19. The apparatus of claim 18,wherein the one or more chemical component sources further comprises: atleast one bulk chemical component container; and at least one buffercontainer having a volume less than the bulk chemical componentcontainer and being in fluid communication with an associated bulkchemical component container and the metering pump.
 20. The apparatus ofclaim 17, wherein at least two of the one or more processing cellscomprise electrochemical plating cells.
 21. The apparatus of claim 17,wherein at least one of the one or more processing cells comprise a spinrinse dry processing cell.
 22. The apparatus of claim 17, wherein atleast one of the one or more processing cells comprise a substrate beveledge clean processing cell.
 23. The apparatus of claim 17, furthercomprising at least one annealing chamber in communication with thesystem platform.
 24. The apparatus of claim 23, wherein the annealchamber includes at least one heating position and at least one coolingposition.
 25. The apparatus of claim 24, wherein the annealing chamberfurther comprises a substrate transfer robot positioned between the atleast one heating position and the at least one cooling position, thesubstrate transfer robot is configured to transfer substrates betweenthe heating and cooling positions.
 26. The apparatus of claim 17,wherein the fluid delivery system is further configured to supply ananolyte to an anode chamber of at least one plating cell positioned onthe system platform.
 27. The apparatus of claim 17, wherein themeasuring the level in the vessel with the ultrasonic signal furthercomprises measuring the temperature in the vessel.
 28. Anelectrochemical processing system, comprising: a processing system basehaving one or more process cell locations thereon; at least twoelectrochemical plating cells positioned at two of the process celllocations; at least one spin rinse dry cell positioned at one of theprocess cell locations; at least one substrate bevel clean cellpositioned at another one of the process cell locations; and a fluiddelivery system in fluid communication with each of the one or moreprocessing cells, the fluid delivery system comprising: one or morechemical component sources; a metering pump in fluid communication witheach of the chemical component sources; a first virgin electrolytesource in fluid communication with the metering pump; and a vessel influid communication with the metering pump at an input and with the oneor more processing cells at an output, the vessel comprising a chargingcell, an ultrasonic sensor, and a controller.
 29. The electrochemicalprocessing system of claim 28, further comprising a factory interface incommunication with the processing system base.
 30. The electrochemicalprocessing system of claim 28, further comprising at least one annealingchamber in communication with at least one of the factory interface andthe processing base.
 31. The electrochemical processing system of claim30, wherein the at least one annealing chamber comprises a heatinglocation, a cooling location, and a robot positioned to transfersubstrates between the heating location and the cooling location. 32.The electrochemical processing system of claim 28, wherein the one ormore plating solution chemical component containers comprise acontainers in fluid communication with a buffer container, the buffercontainer being in fluid communication with the metering pump.
 33. Theelectrochemical processing system of claim 28, wherein the metering pumpcomprises a precise fluid delivery pump having one or more inputs and atleast one output, the metering pump being configured to mix apredetermined ratio of fluid components received at the one or moreinputs and output the predetermined ratio of fluid components from theat least one output.
 34. The electrochemical processing system of claim28, wherein the multiple chemistry plating solution delivery systemfurther comprises a second virgin electrolyte solution container influid communication with the metering pump, the second virginelectrolyte solution-container being configured to provide a secondvirgin electrolyte.
 35. The electrochemical processing system of claim28, wherein the vessel further comprises a temperature measuringapparatus.